The present invention relates to a method and apparatus for treating airway obstructions. More specifically, the present invention relates to a method and apparatus for reducing the volume of the turbinates in order reduce nasal airway obstructions.
Sleep-apnea syndrome is a medical condition characterized by daytime hypersomnomulence, morning arm aches, intellectual deterioration, cardiac arrhythmias, snoring and thrashing during sleep. It is caused by frequent episodes of apnea during the patient""s sleep. The syndrome is classically subdivided into two types. One type, termed xe2x80x9ccentral sleep apnea syndromexe2x80x9d, is characterized by repeated loss of respiratory effort. The second type, termed obstructive sleep apnea syndrome, is characterized by repeated apneic episodes during sleep resulting from obstruction of the patient""s upper airway or that portion of the patient""s respiratory tract which is cephalad to, and does not include, the larynx.
Treatment thus far includes various medical, surgical and physical measures to unobstruct the airways. Medical measures include the use of medications such as protriptyline, medroxyprogesterone, acetazolamide, theophylline, nicotine and other medications in addition to avoidance of central nervous system depressants such as sedatives or alcohol. The medical measures above are sometimes helpful but are rarely completely effective. Further, the medications frequently have undesirable side effects.
Surgical interventions have included uvulopalatopharyngoplasty, tonsillectomy, surgery to correct severe retrognathia and tracheostomy. Other surgical procedures include pulling the tongue as forward as possible and surgically cutting and removing sections of the tongue and other structures which can close off the upper airway passage. These procedures may be effective but the risk of surgery in these patients can be prohibitive and the procedures are often unacceptable to the patients.
Among the air passageways in the body that can become obstructed are the nasal passageways leading from the nose to the pharynx. There are three nasal passageways, namely the inferior, middle and superior nasal meatus. The turbinates, also referred to as nasal concha, are a series of tissues which form at least a portion of these nasal passageways. Forming a portion of the inferior nasal meatus is the inferior nasal concha. The inferior and middle nasal concha each form a portion of the middle nasal meatus. The middle and superior nasal concha each form a portion of the superior nasal meatus. When the inferior, middle and/or superior nasal concha become enlarged, the various nasal meatus which allow air to pass through the nose into the pharynx can become obstructed.
Opening of obstructed nasal airways by reducing the size of the turbinates has been performed using surgical and pharmaceutical treatments. Examples of surgical procedures include anterior and posterior ethmoidectomy, such as those described in xe2x80x9cEndoscopic Paranasal Sinus Surgeryxe2x80x9d by D. Rice and S. Schaefer, Raven Press, 1988); the writings of M. E. Wigand, Messerklinger and Stamberger; and U.S. Pat. No. 5,094,233. For example, as described in U.S. Pat. No. 5,094,233, the Wigand procedure involves the transection of the middle turbinate, beginning with the posterior aspect, visualization of the sphenoid ostium and opening of the posterior ethmoid cells for subsequent surgery. In the sphenoidectomy step, the ostium of the sphenoid is identified and the anterior wall of the sinus removed. Following this step, the posterior ethmoid cells may be entered at their junction with the sphenoid and the fovea ethmoidalis can be identified as an anatomical landmark for further dissection. In anterior ethmoidectomy, the exenteration of the ethmoids is carried anteriorly to the frontal recess. Complications, such as hemorrhage, infection, perforation of the fovea ethmoidalis or lamina papyracea, and scarring or adhesion of the middle turbinate, are reported in connection with these procedures.
A particular problem encountered has been postoperative adhesion occurring between the turbinates and adjacent nasal areas, such as medial adhesion to the septum and lateral adhesion to the lateral nasal wall in the area of the ethmoid sinuses. Otherwise successful surgical procedures may have poor results in these cases. Some surgeons have proposed amputation of a portion of the turbinate at the conclusion of surgery to avoid this complication, resulting in protracted morbidity (crust formation and nasal hygiene problems). The turbinate adhesion problem detracts from these endoscopic surgical procedures. Efforts have been made to reduce the complications associated with the surgical treatment of turbinate tissue, for example by the use of a turbinate sheath device. U.S. Pat. No. 5,094,233.
U.S. Pat. No. 3,901,241 teaches a cryosurgical instrument which is said to be useful for shrinking nasal turbinates. U.S. Pat. No. 3,901,241.
Pharmaceuticals have also been developed for reducing the size of the turbinates. However, pharmaceuticals are not always completely efficacious and generally do not provide a permanent reduction in turbinate size. In addition, pharmaceuticals can have adverse side effects.
A need exists for a method and device for clearing obstructed nasal passageways. It is preferred that the method and device be performable with minimal surgical intervention or post operative complications. It is also preferred that the method and device be performable so as to reduce the size of the turbinates without the surgical cutting or removal of tissue. It is also preferred that the method and device provide a permanent reduction in turbinate size.
An apparatus is provided for ablating at least a portion of a nasal concha. In one embodiment, the apparatus includes a catheter having a distal portion with a dimension configured for positioning the catheter distal portion through a nostril of a patient into a nasal meatus adjacent a surface of a nasal concha, an expandable member positioned at the catheter distal portion, an energy delivery device positioned at the catheter distal portion for delivering ablative energy to the surface of the nasal concha, and a lumen positioned within the catheter for delivering a medium into the expandable member to expand the expandable member.
The present invention also relates to an apparatus for ablating a selected portion of a nasal concha. In this embodiment, the apparatus includes a catheter having a distal portion with a dimension configured for positioning the catheter distal portion through a nostril of a patient into a nasal meatus adjacent a surface of a nasal concha, an energy delivery device for delivering ablative energy positioned at the catheter distal portion, and an insulator positioned to cause delivery of ablative energy to a selected portion of a nasal concha while insulating other tissue forming the nasal meatus from the ablative energy.
The present invention also relates to an apparatus for ablating an internal section of a nasal concha. According to this embodiment, the apparatus includes a catheter having a distal portion with a dimension configured for positioning the catheter distal portion through a nostril of a patient into a nasal meatus adjacent a surface of a nasal concha, an expandable member positioned at the catheter distal portion, an energy delivery device for delivering ablative energy positioned at the catheter distal portion, a lumen positioned within the catheter for delivering a medium into the expandable member to expand the expandable member to adjacent a surface of the nasal concha, and a medium source for delivering medium of a sufficiently low temperature to cool the surface of the nasal concha during energy delivery. According to this embodiment, the energy used should be of a type which can penetrate into an internal section of tissue and cause ablative heating therein. Examples of this type of energy included electromagnetic energy (RF, microwave) and ultrasonic.